Early in the new documentary Pandora's Promise, British environmental writer Mark Lynas travels to the Japanese town of Fukushima, now famous as the site of a 2011 nuclear meltdown. Lynas is a longtime nuclear critic who has since rethought his opposition to atomic power. Dressed in protective equipment and carrying a radiation detector, Lynas roams the spooky, abandoned streets of Fukushima. The desolation is apparent, and it touches even a staunch atomic advocate like Lynas. "There's no other energy source that does this, leaves huge areas contaminated by its strange invisible presence," he says. "I could see why we'd want to...